Speaker
Description
Low-noise cryogenic environments are crucial for operating sensitive quantum devices and detectors. The Colorado Underground Research Institute (CURIE) is an underground laboratory under ~200 m of rock that is being built to provide these low-noise environments. A dry dilution refrigerator (DR) is one technology that would be included in this lab, which offers ease of operation and reduced cost for creating cryogenic environments. These DRs make use of a pulse tube cryocooler to achieve this; however, these pulse tubes come with increased vibrational noise. The Maybell Quantum DR implements vibration isolators and an internal suspension system designed to mitigate this vibrational noise.
We present a characterization of the vibrational noise in this Maybell Quantum cryostat using several vibration sensors, including piezoelectric accelerometers and geophones. Measurements are taken across all three axes and varying temperatures. We provide a detailed description of the sensor thermalization, measurement procedure, and low-noise readout electronics employed. The collected vibration data are analyzed to determine the spectral noise characteristics in the 1 Hz to 1000 Hz frequency range. Transfer functions and correlations between sensors are analyzed to differentiate noise sources. To further disentangle noise sources, we present an initial triple axis SQUID magnetometer setup intended for future cross-correlation with the vibration measurements.